Plant pathogens are of great economic importance, as plant disease accounts for a significant fraction of crop losses. The present invention provides a method of making plants with enhanced resistance to infection with plant pathogens, including viral pathogens, bacterial pathogens, and fungal pathogens.
The present invention provides a method of preparing plants with enhanced resistance to infection with plant pathogens. The method comprises transforming a plant cell with a DNA construct which comprises an exogenous SNF-1 transgene, i.e., a DNA which encodes an SNF-1 protein kinase or the catalytic domain of such kinase. The transgene also comprises a promoter which regulates expression of the SNF-1 kinase or the catalytic domain. The promoter is operably linked to the DNA sequence which encodes the SNF-1 kinase or catalytic domain. The method further comprises the step of generating a transformed plant from the transformed plant cell. The transformed plant expresses the SNF-1 kinase or the catalytic domain and, thus, contains an SNF-1 kinase or catalytic domain that is encoded by the SNF-1 transgene as well as the SNF-1 kinase that is encoded by the plants own SNF-1 gene. Such plants are referred to as xe2x80x9coverexpressors.xe2x80x9d The present method is especially useful for producing plants with enhanced resistance to plant pathogens, particularly viral pathogens, more particularly Geminiviruses. It is expected that the present method is also useful for producing plants with enhanced resistance to abiotic stress. Examples of abiotic stress are ozone, heat stress, and salt stress.
The present invention also provides a plant cell having a SNF-1 transgene stably integrated into its genome. The transgene comprises a DNA sequence encoding a SNF-1 kinase or the catalytic domain of such kinase and a promoter which controls expression of the DNA coding sequence in the plant cell. The present invention also relates to cell cultures consisting of such transformed cells, plants regenerated from such transformed cells and seeds of such transformed plants.